OK spoke too soon. At Cubase>Studio Setup, under Remote Devices and the added Mackie Control>MIDI Input, There was no option for 'MIDIIN2 (KeyLab mkII 88)' only 'KeyLab mkII 88' which was what I had selected and did not work. So in order to get the option to appear, I did the following:
@ Cubase>Studio Setup>MIDI Port Setup, at the row "Windows MIDI/In/MIDIIN2 (KeyLab mkII 88), under the column "In 'All MIDI" I had to uncheck the box. Once that was done I was able to go back to Cubase>Studio Setup, under Remote Devices>Mackie Control>MIDI Input, and the option for MIDIIN2 (KeyLab mkII 88) was there. I selected it and all is RIGHT WITH THE WORLD..... well according to my software anyway!